LAMMPS (28 Mar 2023 - Development)
dimension       2
units           micro
atom_style      sph

variable        R equal 0.5             # radius of sphere          micrometers
variable        a equal $R/5            # lattice spacing           micrometers
variable        a equal 0.5/5            
variable        Lf equal $R*3
variable        Lf equal 0.5*3
variable        Lb equal $R*4
variable        Lb equal 0.5*4
variable        wall_velocity equal 0.01                          # micrometers/microsecond
variable        T equal 300.
variable        rho_0 equal 1.          # density                   picograms/micrometer^3
variable        c_0 equal 100.          # speed of sound            micrometers/microsecond
variable        mu equal 1.             # dynamic viscosity         picogram/(micrometer-microsecond)
variable        h equal $a*4.5          # kernel function cutoff    micrometers
variable        h equal 0.1*4.5          
variable        mass equal $a*$a*$a*${rho_0}
variable        mass equal 0.1*$a*$a*${rho_0}
variable        mass equal 0.1*0.1*$a*${rho_0}
variable        mass equal 0.1*0.1*0.1*${rho_0}
variable        mass equal 0.1*0.1*0.1*1
variable        dt equal 1e-3           # timestep                  microseconds
variable        skin equal 0.2*$h
variable        skin equal 0.2*0.45

region          box block -${Lb} ${Lb} -${Lb} ${Lb} 0 ${a} units box
region          box block -2 ${Lb} -${Lb} ${Lb} 0 ${a} units box
region          box block -2 2 -${Lb} ${Lb} 0 ${a} units box
region          box block -2 2 -2 ${Lb} 0 ${a} units box
region          box block -2 2 -2 2 0 ${a} units box
region          box block -2 2 -2 2 0 0.1 units box
create_box      4 box
Created orthogonal box = (-2 -2 0) to (2 2 0.1)
  2 by 2 by 1 MPI processor grid
lattice         sq $a
lattice         sq 0.1
Lattice spacing in x,y,z = 0.1 0.1 0.1

create_atoms    1 box
Created 1600 atoms
  using lattice units in orthogonal box = (-2 -2 0) to (2 2 0.1)
  create_atoms CPU = 0.001 seconds

region          sphere sphere 0 0 0 $R units box
region          sphere sphere 0 0 0 0.5 units box
set             region sphere type 2
Setting atom values ...
  81 settings made for type

region          upper_wall block INF INF +${Lf} INF INF INF units box
region          upper_wall block INF INF +1.5 INF INF INF units box
set             region upper_wall type 3
Setting atom values ...
  200 settings made for type

region          lower_wall block INF INF INF -${Lf} INF INF units box
region          lower_wall block INF INF INF -1.5 INF INF units box
set             region lower_wall type 4
Setting atom values ...
  240 settings made for type

group           fluid type 1
1079 atoms in group fluid
group           sphere type 2
81 atoms in group sphere
group           upper_wall type 3
200 atoms in group upper_wall
group           lower_wall type 4
240 atoms in group lower_wall

mass            * ${mass}
mass            * 0.001
set             group all sph/rho ${rho_0}
set             group all sph/rho 1
Setting atom values ...
  1600 settings made for sph/rho

pair_style      sdpd/taitwater/isothermal $T ${mu} 76787    # temperature viscosity random_seed
pair_style      sdpd/taitwater/isothermal 300 ${mu} 76787    
pair_style      sdpd/taitwater/isothermal 300 1 76787    
pair_coeff      * * ${rho_0} ${c_0} ${h}
pair_coeff      * * 1 ${c_0} ${h}
pair_coeff      * * 1 100 ${h}
pair_coeff      * * 1 100 0.45

fix             1 fluid sph
fix             2 sphere rigid/meso single
  1 rigid bodies with 81 atoms
fix             3 upper_wall meso/move linear +${wall_velocity} 0 0 units box
fix             3 upper_wall meso/move linear +0.01 0 0 units box
fix             4 lower_wall meso/move linear -${wall_velocity} 0 0 units box
fix             4 lower_wall meso/move linear -0.01 0 0 units box

fix             2d all enforce2d

neighbor        ${skin} bin
neighbor        0.09 bin
neigh_modify	delay 0 every 1 check yes
timestep        ${dt}
timestep        0.001

dump            dump_id all atom 100 dump.lammpstrj

thermo          100
thermo_style    custom step time nbuild ndanger

run             10000
Generated 0 of 6 mixed pair_coeff terms from geometric mixing rule
Neighbor list info ...
  update: every = 1 steps, delay = 0 steps, check = yes
  max neighbors/atom: 2000, page size: 100000
  master list distance cutoff = 0.54
  ghost atom cutoff = 0.54
  binsize = 0.27, bins = 15 15 1
  1 neighbor lists, perpetual/occasional/extra = 1 0 0
  (1) pair sdpd/taitwater/isothermal, perpetual
      attributes: half, newton on
      pair build: half/bin/atomonly/newton
      stencil: half/bin/2d
      bin: standard
Per MPI rank memory allocation (min/avg/max) = 7.23 | 7.23 | 7.23 Mbytes
   Step          Time        Nbuild      Ndanger  
         0   0                      0           0 
       100   0.1                    0           0 
       200   0.2                    0           0 
       300   0.3                    0           0 
       400   0.4                    1           0 
       500   0.5                    1           0 
       600   0.6                    1           0 
       700   0.7                    2           0 
       800   0.8                    2           0 
       900   0.9                    2           0 
      1000   1                      3           0 
      1100   1.1                    3           0 
      1200   1.2                    3           0 
      1300   1.3                    4           0 
      1400   1.4                    4           0 
      1500   1.5                    4           0 
      1600   1.6                    5           0 
      1700   1.7                    5           0 
      1800   1.8                    5           0 
      1900   1.9                    6           0 
      2000   2                      6           0 
      2100   2.1                    6           0 
      2200   2.2                    7           0 
      2300   2.3                    7           0 
      2400   2.4                    7           0 
      2500   2.5                    8           0 
      2600   2.6                    8           0 
      2700   2.7                    8           0 
      2800   2.8                    9           0 
      2900   2.9                    9           0 
      3000   3                      9           0 
      3100   3.1                   10           0 
      3200   3.2                   10           0 
      3300   3.3                   10           0 
      3400   3.4                   11           0 
      3500   3.5                   11           0 
      3600   3.6                   11           0 
      3700   3.7                   12           0 
      3800   3.8                   12           0 
      3900   3.9                   12           0 
      4000   4                     13           0 
      4100   4.1                   13           0 
      4200   4.2                   13           0 
      4300   4.3                   14           0 
      4400   4.4                   14           0 
      4500   4.5                   14           0 
      4600   4.6                   14           0 
      4700   4.7                   15           0 
      4800   4.8                   15           0 
      4900   4.9                   16           0 
      5000   5                     16           0 
      5100   5.1                   16           0 
      5200   5.2                   17           0 
      5300   5.3                   17           0 
      5400   5.4                   17           0 
      5500   5.5                   18           0 
      5600   5.6                   18           0 
      5700   5.7                   18           0 
      5800   5.8                   19           0 
      5900   5.9                   19           0 
      6000   6                     20           0 
      6100   6.1                   20           0 
      6200   6.2                   20           0 
      6300   6.3                   21           0 
      6400   6.4                   21           0 
      6500   6.5                   21           0 
      6600   6.6                   22           0 
      6700   6.7                   22           0 
      6800   6.8                   22           0 
      6900   6.9                   23           0 
      7000   7                     23           0 
      7100   7.1                   23           0 
      7200   7.2                   24           0 
      7300   7.3                   24           0 
      7400   7.4                   24           0 
      7500   7.5                   25           0 
      7600   7.6                   25           0 
      7700   7.7                   25           0 
      7800   7.8                   25           0 
      7900   7.9                   26           0 
      8000   8                     26           0 
      8100   8.1                   26           0 
      8200   8.2                   27           0 
      8300   8.3                   27           0 
      8400   8.4                   28           0 
      8500   8.5                   28           0 
      8600   8.6                   28           0 
      8700   8.7                   29           0 
      8800   8.8                   29           0 
      8900   8.9                   29           0 
      9000   9                     30           0 
      9100   9.1                   30           0 
      9200   9.2                   30           0 
      9300   9.3                   31           0 
      9400   9.4                   31           0 
      9500   9.5                   31           0 
      9600   9.6                   32           0 
      9700   9.7                   32           0 
      9800   9.8                   32           0 
      9900   9.9                   32           0 
     10000   10                    33           0 
Loop time of 24.8261 on 4 procs for 10000 steps with 1600 atoms

Performance: 34802055.618 ns/day, 0.000 hours/ns, 402.802 timesteps/s, 644.483 katom-step/s
99.1% CPU use with 4 MPI tasks x no OpenMP threads

MPI task timing breakdown:
Section |  min time  |  avg time  |  max time  |%varavg| %total
---------------------------------------------------------------
Pair    | 21.84      | 22.879     | 23.944     |  21.4 | 92.16
Neigh   | 0.007446   | 0.0079435  | 0.0084435  |   0.6 |  0.03
Comm    | 0.5271     | 1.5894     | 2.6259     |  80.9 |  6.40
Output  | 0.034799   | 0.035302   | 0.036437   |   0.4 |  0.14
Modify  | 0.20079    | 0.21033    | 0.2202     |   1.7 |  0.85
Other   |            | 0.1041     |            |       |  0.42

Nlocal:            400 ave         414 max         390 min
Histogram: 2 0 0 0 0 1 0 0 0 1
Nghost:          555.5 ave         564 max         543 min
Histogram: 1 0 0 0 1 0 0 0 0 2
Neighs:        18299.2 ave       18820 max       17906 min
Histogram: 1 1 0 0 0 0 1 0 0 1

Total # of neighbors = 73197
Ave neighs/atom = 45.748125
Neighbor list builds = 33
Dangerous builds = 0
Total wall time: 0:00:24
